1. Field of the Invention
The present invention relates to a resuscitation valve for supplying oxygen or an air/oxygen mixture to the airway of a patent or other individual as determined by an operator.
2. Description of the Prior Art
In instances of cardiac arrest or cessation of spontaneous breathing, emergency life support measures require a means to revive a patient""s breathing function. This is most often accomplished by the use of a manually operated resuscitation device. These devices are powered by a high pressure oxygen or oxygen/air mixture source and administer the breathable gas either in response to the manually operable actuator device or in response to the commencement of the patient""s natural breathing cycle when breathing is restored.
Such oxygen powered, manually operated demand valves are commonly used by emergency medical teams in the United States and other countries for resuscitating victims in heart and pulmonary distress. Such devices are typified by the arrangements described in U.S. Pat. No. 3,795,257, of which I am a co-inventor.
These devices contain many small and complex parts and are priced so as to make it impractical to consider them for single patient use (i.e., disposable devices). As a result it is necessary to sanitize these devices after each use and to routinely check and repair them.
The complexity of these prior art devices derives from their function as a demand valve, i.e., providing the patient with the oxygen or oxygen/air mixture frm the high pressure source when the breathing cycle is restored. In reality however, they are seldom used for this function. In the normal course of treatment, when spontaneous breathing is established, a simple continuous flow system is used to supply supplemental oxygen to the patient. Thus, the demand valve resuscitator is typically only used to establish spontaneous breathing.
There is a need for a simple and inexpensive device that will function to resuscitate the non-breathing patient according to xe2x80x9cAHAxe2x80x9d (American Heart Association) guidelines while accommodating a patient""s spontaneous breathing.
A resuscitation valve assembly achieving the above goals includes a housing having an inlet port adapted to be connected to a patient""s airway, an inhalation chamber within the housing, an outlet port and an ambient air port. A manually operated valve is mounted in the housing, e.g., within a centrally located tubular section which includes an axial bore in fluid communication with the inhalation chamber and terminating at one end at the inlet port. The valve preferably includes a plunger, which when manually depressed to a first position, dislodges a ball from an annular seat within the bore to connect the inhalation chamber to a source of pressurized oxygen or oxygen/air mixture. The plunger is normally retained in a second position, e.g., by means of a spring, to allow the gas from the high pressure source to force the ball against the annular seat and close the inlet port. The inhalation chamber is disconnected from the pressurized breathable gas source when the valve is in its second position.
An inhalation/exhalation check valve is disposed within the housing and adjacent the outlet and ambient air ports for allowing gas at above ambient air pressure within the inhalation chamber to pass through the outlet port and enter a patient""s airway and for venting the individual""s exhaled gas through the ambient air port. Means, which may comprise the inhalation/exhalation valve, functions in response to a sub-atmospheric pressure within the outlet port, due to the patient""s spontaneous breathing, to allow ambient air to enter the patient""s airway. The resuscitation valve preferably includes a pressure relief valve to set the maximum pressure within the inhalation chamber and an alarm responsive to an over pressure condition.
The resuscitation valve of my invention may comprise fewer than ten molded plastic parts and biasing means such as springs for the plunger and relief valve. The assembly is sufficiently simple and inexpensive to manufacture to be disposable after a single use thereby eliminating the time and considerable expense of sanitizing, testing and repairing required of the prior art devices.